/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2001-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: Comment.java,v 1.2.4.1 2005/09/01 12:02:37 pvedula Exp $
 */

package com.sun.org.apache.xalan.internal.xsltc.compiler;

import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.GETFIELD;
import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;
import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
import com.sun.org.apache.bcel.internal.generic.PUSH;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;

/**
 * @author Jacek Ambroziak
 * @author Santiago Pericas-Geertsen
 * @author Morten Jorgensen
 */
final class Comment extends Instruction {

  public void parseContents(Parser parser) {
    parseChildren(parser);
  }

  public Type typeCheck(SymbolTable stable) throws TypeCheckError {
    typeCheckContents(stable);
    return Type.String;
  }

  public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // Shortcut for literal strings
    Text rawText = null;
    if (elementCount() == 1) {
      Object content = elementAt(0);
      if (content instanceof Text) {
        rawText = (Text) content;
      }
    }

    // If the content is literal text, call comment(char[],int,int) or
    // comment(String), as appropriate.  Otherwise, use a
    // StringValueHandler to gather the textual content of the xsl:comment
    // and call comment(String) with the result.
    if (rawText != null) {
      il.append(methodGen.loadHandler());

      if (rawText.canLoadAsArrayOffsetLength()) {
        rawText.loadAsArrayOffsetLength(classGen, methodGen);
        final int comment =
            cpg.addInterfaceMethodref(TRANSLET_OUTPUT_INTERFACE,
                "comment",
                "([CII)V");
        il.append(new INVOKEINTERFACE(comment, 4));
      } else {
        il.append(new PUSH(cpg, rawText.getText()));
        final int comment =
            cpg.addInterfaceMethodref(TRANSLET_OUTPUT_INTERFACE,
                "comment",
                "(" + STRING_SIG + ")V");
        il.append(new INVOKEINTERFACE(comment, 2));
      }
    } else {
      // Save the current handler base on the stack
      il.append(methodGen.loadHandler());
      il.append(DUP);             // first arg to "comment" call

      // Get the translet's StringValueHandler
      il.append(classGen.loadTranslet());
      il.append(new GETFIELD(cpg.addFieldref(TRANSLET_CLASS,
          "stringValueHandler",
          STRING_VALUE_HANDLER_SIG)));
      il.append(DUP);
      il.append(methodGen.storeHandler());

      // translate contents with substituted handler
      translateContents(classGen, methodGen);

      // get String out of the handler
      il.append(new INVOKEVIRTUAL(cpg.addMethodref(STRING_VALUE_HANDLER,
          "getValue",
          "()" + STRING_SIG)));
      // call "comment"
      final int comment =
          cpg.addInterfaceMethodref(TRANSLET_OUTPUT_INTERFACE,
              "comment",
              "(" + STRING_SIG + ")V");
      il.append(new INVOKEINTERFACE(comment, 2));
      // Restore old handler base from stack
      il.append(methodGen.storeHandler());
    }
  }
}
